This Asthma and Allergic Diseases Center application, made up of four independent but interrelated projects, proposes to study immunopathogenesis of atopic bronchial asthma, with particular attention to interactions between local inflammatory processes secondary to inhalational allergen challenge, nonspecific bronchial hyperresponsiveness, clinical manifestations of disease and response to treatment. Local changes in cells, antibodies and mediators will be studied longitudinally using the technique of bronchoalveolar lavage. Chopped fresh human lung obtained at thoracotomy for surgical indications will be studied for alterations in beta adrenergic and cholinergic receptors following in vitro anaphylaxis. Longitudinal assessment of laboratory animal workers will evaluate the epidemiology of allergic responsiveness among those newly exposed to atopic allergens, and similar studies will evaluate the development of IgE, IgG and IgA antibodies in individuals newly exposed to ragweed.